Design switching on graphs

Ferdinand Ihringer; Robin Simoens

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arXiv · 2508.11523

Design switching on graphs

Ferdinand Ihringer·Robin Simoens

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Abstract

We show that each (r, lambda)-design yields a class of switching methods that can be used to produce cospectral graphs. We use this to explain several specific switching methods such as Godsil-McKay (GM) switching and Wang-Qiu-Hu (WQH) switching.

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BibTeX RIS

Ferdinand Ihringer, Robin Simoens. 2026-07-29. Design switching on graphs. https://arxiv.org/abs/2508.11523

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